| | | 1 | | // -------------------------------------------------------------------------------- |
| | | 2 | | // Copyright (C) 2025 Eugene Eremeev (also known as Yevhenii Yeriemeieiv). |
| | | 3 | | // All Rights Reserved. |
| | | 4 | | // -------------------------------------------------------------------------------- |
| | | 5 | | // This software is the confidential and proprietary information of Eugene Eremeev |
| | | 6 | | // (also known as Yevhenii Yeriemeieiv) ("Confidential Information"). You shall not |
| | | 7 | | // disclose such Confidential Information and shall use it only in accordance with |
| | | 8 | | // the terms of the license agreement you entered into with Eugene Eremeev (also |
| | | 9 | | // known as Yevhenii Yeriemeieiv). |
| | | 10 | | // -------------------------------------------------------------------------------- |
| | | 11 | | |
| | | 12 | | namespace LeetCode.Algorithms.FindTheLexicographicallyLargestStringFromTheBox1; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public class FindTheLexicographicallyLargestStringFromTheBox1TwoPointers : |
| | | 16 | | IFindTheLexicographicallyLargestStringFromTheBox1 |
| | | 17 | | { |
| | | 18 | | /// <summary> |
| | | 19 | | /// Time complexity - O(n) |
| | | 20 | | /// Space complexity - O(n) |
| | | 21 | | /// </summary> |
| | | 22 | | /// <param name="word"></param> |
| | | 23 | | /// <param name="numFriends"></param> |
| | | 24 | | /// <returns></returns> |
| | | 25 | | public string AnswerString(string word, int numFriends) |
| | 2 | 26 | | { |
| | 2 | 27 | | if (numFriends == 1) |
| | 0 | 28 | | { |
| | 0 | 29 | | return word; |
| | | 30 | | } |
| | | 31 | | |
| | 2 | 32 | | var lastSubstring = GetLastSubstring(word); |
| | | 33 | | |
| | 2 | 34 | | return lastSubstring[..Math.Min(lastSubstring.Length, word.Length - numFriends + 1)]; |
| | 2 | 35 | | } |
| | | 36 | | |
| | | 37 | | private static string GetLastSubstring(string word) |
| | 2 | 38 | | { |
| | 2 | 39 | | var i = 0; |
| | 2 | 40 | | var j = 1; |
| | | 41 | | |
| | 6 | 42 | | while (j < word.Length) |
| | 4 | 43 | | { |
| | 4 | 44 | | var k = 0; |
| | | 45 | | |
| | 7 | 46 | | while (j + k < word.Length && word[i + k] == word[j + k]) |
| | 3 | 47 | | { |
| | 3 | 48 | | k++; |
| | 3 | 49 | | } |
| | | 50 | | |
| | 4 | 51 | | if (j + k < word.Length && word[i + k] < word[j + k]) |
| | 0 | 52 | | { |
| | 0 | 53 | | var t = i; |
| | | 54 | | |
| | 0 | 55 | | i = j; |
| | | 56 | | |
| | 0 | 57 | | j = Math.Max(j + 1, t + k + 1); |
| | 0 | 58 | | } |
| | | 59 | | else |
| | 4 | 60 | | { |
| | 4 | 61 | | j = j + k + 1; |
| | 4 | 62 | | } |
| | 4 | 63 | | } |
| | | 64 | | |
| | 2 | 65 | | return word[i..]; |
| | 2 | 66 | | } |
| | | 67 | | } |